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room addition and adding heat

josephcjosephc Posts: 35Member
we are having a 16ft by 17 ft by 8 ft high tv room addition added onto our home. I have not gotten a firm estimate of required BTUs though the range has been anywhere from 8800 to 12000. Any advice/rules of thumb/direction is appreciated on the calculation (I checked the slantfin site and am trying to use it); located in upstate ny.

my other question is the addition of the heat source. I have a two pipe vapor system/gravity return. My boiler is already large and there is room for more edr. Do most jobs of this scope add on a classic radiator like the rest found in the home or do something else like a steam baseboard or a hydronic loop with circulator? Based on my discussion with builder and the plumber it looks like up to me to get the radiator and give direction.

the existing main and returns have 1 inch supply and 3/4 inch return taps from radiators removed in the past. My initial thoughts are a radiator of 60-70 edr max would give more than enough btu and would be close to limit supplied by the 1 inch pipe. Am I close to knowing what I'm doing?


  • New England SteamWorksNew England SteamWorks Posts: 1,225Member
    My advice is to pipe in steam if at all possible. Adding a hot water loop introduces a lot of unneeded expense and complexity. But, that's likely the route they will push you because it is their comfort zone.

    New England SteamWorks
    Service, Installation, & Restoration of Steam Heating Systems
  • JackJack Posts: 1,044Member
    Look at a Rinnai Energysaver EX-11. Modulates from 5500-11000btu. 2.5" hole for the supplied vent. Very reliable.
  • SteamheadSteamhead Posts: 12,868Member

    My advice is to pipe in steam if at all possible. Adding a hot water loop introduces a lot of unneeded expense and complexity. But, that's likely the route they will push you because it is their comfort zone.

    This. We've done it, and as long as you stay true to the Dead Men's pipe and radiator sizing, it works great.
    All Steamed Up, Inc.
    "Reducing our country's energy consumption, one system at a time"
    Steam, Vapor & Hot-Water Heating Specialists
    Oil & Gas Burner Service
    Baltimore, MD (USA) and consulting anywhere.
  • ZmanZman Posts: 4,811Member
    Your heat loss estimates look high.
    The whole key to this is to get the right steam guy.
    The plumber that want's you to provide direction is a huge red flag. He probably is not the right guy for the job.
    This book will help you understand how to find the right contractor.
    "If you can't explain it simply, you don't understand it well enough"
    Albert Einstein
  • BrewbeerBrewbeer Posts: 575Member
    Seems to me that if staying with steam, you need to calculate the ratio of ERD to heatloss in the other existing rooms, them size your radiation in the new room keeping this ratio in mind. Also, heat loss in the spaces that will be adjoining the new room, will decrease.
    Hydronics inspired homeowner with self-designed high efficiency low temperature baseboard system and professionally installed mod-con boiler with indirect DHW. My system design thread:
    System Photo:
  • brandonfbrandonf Posts: 163Member
    Investing in really good insulation will help lower that heat loss. You can go with a vintage radiator or you can buy brand new although they are very pricey. But nothing beats the comfort.
    Homeowner, Entrepreneur, Mechanic, Electrician,

    "The toes you step on today are connected to the butt you'll have to kiss tomorrow". ---Vincent "Buddy" Cianci
  • josephcjosephc Posts: 35Member
    installed and heating the room well
    6 tube 23 inch high by 18 sections
  • Jamie HallJamie Hall Posts: 10,279Member
    Very nice. Glad you did that!

    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England.

    Hoffman Equipped System (all original except boiler), Weil-Mclain 580, 2.75 gph Carlin, Vapourstat 0.5 -- 6.0 ounces per square inch
  • ethicalpaulethicalpaul Posts: 661Member
    edited November 2018
    Can you link to the radiator you went with? I just bought one from AFSupply and it is comically tiny (although it may heat fine--it has 4 columns and 10 sections, but everything is just like miniatured

    PS: I hope it stays toasty for you, I shudder when I see those added-on rooms with 3 exposed walls and an exposed ceiling on a slab :cold_sweat:
    1 pipe Utica 112 in Cedar Grove, NJ, 1913 coal > oil > NG
  • josephcjosephc Posts: 35Member
    the radiator is a vintage AERO from the 1920s/30s of the same age as the ones in rest of home. I was fortunate to obtain from neighbor.

  • jtwernjtwern Posts: 5Member
    Not only did you heat it the right way, I see you stayed true with the woodwork. Nicely done!
  • ethicalpaulethicalpaul Posts: 661Member
    Awesome! It looks great, I thought it was new! All mine have 14 coats of paint on them
    1 pipe Utica 112 in Cedar Grove, NJ, 1913 coal > oil > NG
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